An endoscopic hemostatic forceps is utilized to apply a high-frequency current to a pair of high-frequency electrodes pinching a biological tissue therebetween to thereby coagulate the biological tissue by cauterization. In the case where the high-frequency electrodes contacting the biological tissue have a large area, it takes a long time before the contact portion is sufficiently heated for attaining a hemostatic effect. In this case, the biological tissue suffers a deep burn therein over an extensive area thus suffering unnecessary tissue destruction, while the hemostatic effect, which is the object of the treatment, cannot be attained as desired. Accordingly, a forceps type high-frequency treatment instrument has been proposed that includes a pair of forceps cups constituted of a conductive metal that serves as high-frequency electrodes and configured to be able to change into a state where front portions of the pair of forceps cups are open, and a state where the pair of forceps cups are close, the forceps cups being provided with an electrically insulative coating over an entirety thereof, except for an outer periphery of the closing-side surface of the respective forceps where the conductive metal is exposed (see, for example, patent document 1).